Apparatus for the manufacture of corrugated reenforced asbestos sheets or plates



June 27, 1933. A. H. ARENTSEN 1,915,510

APPARATUS FOR THE MANUFACTURE OF CORRUGATED REENFORCED ASBESTOS SHEETSOR PLATES Original Filed Aug. 14, 1929 l J u iLJLIl'Il u u/ t k iPatented June 27, i933 UNITED STATES PATENT OFFICE ABE HEBMANUSARENTSEN, OF AMSTERDAM, NETHERLANDS AIEPAR-ATUS roa 'rrm mnrnc'runn orconauea'rnn nnmvroncnn .asnnsros snnn'rs on. PLATES Original applicationfiled August 14, 1929, Serial 1T0. 885,930, and in the Netherlands andGermany Iay 16, 1929. Divided and this application filed ioctober 21,1931. Serial Ito/570,206.

Processes are known whereby both sides of an insertion of jute, cloth orwire are coated with a mixture of asbestos, zinc-oxide, cement and asolution of glue, and the sheets 5 thus obtained are freed from liquidsubstances by pressure and are then dried.

This process, however, has not proved a success in practice, because thecomposition of the mixture is, in consequence of the use of zinc-oxideand of the large quantity of asbestos much too expensive and alsobecause the application of the mixture to the inserted material isdifficult and very slow. Moreover it is very often the case that theinserted pointed out that the so-called circular sieve.

and joggling machines which are employed for the manufacture of theusual asbestos eement plates or sheets without insertions are absolutelyunsuitable for the manufacture of such sheets or plates with iron wireinsertions.

According to the present invention which 0 eliminates the abovementioned defects the cement and asbestos are mixed together with waterin certain proportions with or without an admixture of colouring matterto a thick paste, which paste is applied to both sides of an iron wirenetting or gauze. The netting orgauze is then passed centrally betweenone or more pairs of rollers arranged in. sequence,

whereby the paste is pressed through and around the meshes of the wirenetting by 40 means of rollers spaced at a distance from one another,the excess water being then removed by means of one or more pairs ofrollers, whereupon the continuous sheet of asbestos cement is rolled orpressed out to the desired thickness. After the terminationofthisprocess further layers of iron wire netting may be applied to bothsides of the asbestos cement sheet as previously manufactured, these newlayers of netting being again embedded in asbestos cement, whereupon theexcess water is removed by pressing. The process may, if required, berepeated several times. Finally before-the asbestos cement sheetis quitedry' it may be passed between pairs of corrugated or fluted rollers,arranged in. point form, in

- such a manner that in the first instance two corrugations are formedin the middle of the sheet whereupon further corrugations are ler%th.

or the purpose of explaining the rocess according to the invention moreclear y, reference is made to the attached drawing in which Fig. 1 is adiagrammatic viewshowing the operations for the manufacture ofcontinuous asbestos cement sheet with a reen-' forcing iron wire nettinginsertion or insertions and Figs. 2 and 3 schematically illustrate themanufacturing process for corru;

gated plates or sheets.

The process consists in mixing together cement and asbestos, preferablyasbestos of short fibres in a proportion say 7 1 with suflicient waterto make a thick aste. If it is desired to produce coloure sheets orplates,.then the desired colouring matter is worked into and thoroughlymixed with this paste. This asbestos cement plate, which containscomparatively little water-is then applied to both sides of a continuousband or web of iron netting 2, this iron wire netting sheet is passed inits vertical position smoothly and centrally between two or more pairsof rolls 1 arranged one behind the other,

the rolls being arranged the same distance v from one another. The rolls1 are vided with vertically projecting edges w ile the surfaces of therolls are prefera 1y made of metal gauze, for the purpose of enablingthe water to escape through the meshes of this gauze surface. Theasbestos cement mass 3 is pressed by means of the rolls between,

through and around the meshes of the iron wire netting 2 and itconsequently encloses the meshes completely. A second pair of rolls4,,which is preferably designed and J constructed similarly to the pairof rolls 1,

forces the excess water out of the mass and at the same time rolls thecontinous asbestos cement sheet to the desired thickness. If it isrequired, several pairs of rollers 4 may be 5 provided.

If it is desired to manufacture continuous asbestos cement sheets withseveral insertions of iron wire netting, the iron wire netting bands 5are applied again to both sides of 3 the asbestos cement band or sheet7' already produced and these new insertions are again coated withasbestos cement paste 6. The continuous asbestos cement sheet 7originally manufactured together with the iron wire netting sheets 5applied to both its sides with their respective asbestos coatings 6 arethen passed between one or more pairs of rollers 8.

For the purpose of forcing the water out of the outer coatings and alsofor the purpose of rolling the continuous sheet 9 to the colour.

If corrugated plates are required, then the continuous asbestos sheet 9is before it is quite dry passed between pairs of fluted rolls 10arranged in pointed form, in such a mannor, that in the first instancetwo corrugations are rolled into the middle of the continuous sheet, andthereafter other corrugations are rolled into the continuous sheet oneither side of the previously formed corrugations and so on until thesheet is corrugated throughout its whole width. Finally the corrugatedplates or sheets may be passed through between one or more pairs offluted rolls so as to accentuate the shape of the corrugations.

When the continuous sheet 9 is clamped or held by the first pair ofrolls 10 it is cut off to the desired length.

The continuous asbestos cement sheet or the corrugated asbestos cementplates may after they have been scored be bent to any angle,

while after the score has been filled the thickness of the sheet orplate, remains the same as it was before. The corrugations formed in theplate remain in it even after it has been cut off, as the wire nettingacquires the corrugated shape imparted to the plate.

remains in a good condition because of its quick application.

The lateral edges of the continuous sheet stand accurately at rightangles to the plane of the sheet. The sheet has therefore no water edgesas inthe case with the hitherto known asbestos cement plates or wireinsertion. The two sides of the sheet are perfectly smooth, as the massis moulded by means of rolls and as no felt bedding is used in themanufacturing process.

It is self evident that the asbestos cementplates or sheets with ironwire netting can be used for numerous purposes, especially in such caseswhere the usual asbestos. cement plates without any wire reenforcementare useless because they do not possess sufficient carrying or tensilestrength.

This application covers the apparatus for carrying out my novel process,which has been claimed in application No. 385,930, filed August 14,1929, of which this is a division and which has become Patent 1,864,626.

I claim as my invention:

1. An apparatus for the manufacture of cprrugated plates comprising aset of hor1- zontally disposed rolls of uniform length adapted tosupport an uncorrugated plate throughout its entire width, a second setof rollers disposed above said supporting rollers, said second set ofrollers being of a length less than that of the supporting rollers andbeing fluted and arranged in tapered formation and said first named setof rollers having fluted portions similarly arranged and oppositelydisposed to said second named rollers, whereby corrugations are firstformed in the center of the sheet and then other corrugations on eitherside of the middle to progressively corrugate the plate throughout itsentire width.

2. An apparatus for the manufacture of corrugated asbestos platesreenforced with woven metal insertions, comprising a plurality of upperand lower rollers provided with corrugations, the upper rollers being ofconsiderable less length than the lower rollers, and being arranged instaggered V- shaped formation, and means for forcing incompletely driedasbestos plates between the upper and lower rollers, the arrangement of.the upper rollers being such that the plates receive corrugations firstin a section of the middle, and then receive corrugations in sections oneach side of the middle until the whole plate is corrugated.

. -In testimony whereof, I afiix my signature.

ARIE HERMANUS ARENTSEN.

